Sure, there’s a technical answer: the carefully curated blend of repetition, earworms, and the mind-control tactics of Max Martin and the Illuminati. But there’s another thing happening beneath the surface. Pop music represents us — specifically, who we were, as a society, at the precise moment you heard that song for the 1,000th time in a day. What we were into. What we weren’t. What mattered. The weird stuff we liked in bed. It’s all in there, and it’s the real reason some songs are hits, and others are Britney Spears-Iggy Azalea songs.